/*
 * Copyright (c) 2019 DuckDuckGo
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.duckduckgo.app.global.uri

import android.net.Uri

fun Uri.removeSubdomain(): String? {
    val host = host ?: return null

    val splitDomains = host.split(".")
    if (splitDomains.isEmpty()) return null

    val newHost = removeFirstSubdomain(splitDomains)
    if (!isValid(newHost)) return null

    return appendScheme(newHost)
}

private fun removeFirstSubdomain(splitDomains: List<String>): String {
    return splitDomains
        .drop(1)
        .joinToString(".")
}

private fun isValid(uri: String): Boolean {
    if (!uri.contains(".")) {
        return false
    }
    return true
}

private fun Uri.appendScheme(newHost: String): String? {
    return if (scheme == null) {
        newHost
    } else {
        "$scheme://$newHost"
    }
}
